Intermediate phase asphalt raw material for producing carbon fibers and preparation method thereof

Abstract

The present invention relates to an intermediate phase asphalt raw material for producing carbon fibers and a preparation method thereof, wherein the intermediate phase asphalt raw material intermediate phase content determined through the polarizing microscope method is 100%, S1/S2 in the infrared absorption spectrogram of the intermediate phase asphalt is more than 1.7, S1 is the area of the absorption peak at the wavelength of 2800-2990 cm<-1>, S2 is the area of the absorption peak at the wavelength of 2990-3150 cm<-1>, S3/S4 in the <13>C nuclear magnetic resonance spectrogram of the intermediate phase asphalt is less than 19, S3 is the area of the absorption peak with the chemical shift of 23.8-58.0 ppm, and S4 is the area of the absorption peak with the chemical shift of 8.0-23.8 ppm. According to the present invention, methylnaphthalene and other naphthalene compounds are adopted as raw materials, hydrogen fluoride-boron trifluoride is adopted as a catalyst, and the polymerization conditions are controlled to prepare the intermediate phase asphalt. Compared with the intermediate phase asphalt in the prior art, the intermediate phase asphalt of the present invention has characteristics of excellent spinnability, excellent pre-oxidation property and simple preparation process control, and can be adopted as the industrial production raw material of the high strength and high modulus asphalt-base carbon fibers.

Description

technical field [0001] The invention relates to the field of carbon industry, in particular to a mesophase pitch raw material suitable for preparing high-performance carbon fibers with excellent preoxidation performance and a preparation method. Background technique [0002] High-performance carbon fiber is light, has high strength and high elastic modulus, and plays a huge role as a high-value material in the fields of defense industry, aerospace, cutting-edge technology, pillar industry, and daily life. The demand for high-performance carbon fiber is increasing. The rate of greater than 10% has increased significantly year by year. [0003] According to the classification of raw materials used, carbon fiber can be divided into polyacrylonitrile-based (PAN) carbon fiber, pitch-based carbon fiber and viscose-based carbon fiber. At present, carbon fiber products are mainly the first two types, of which PAN-based carbon fiber accounts for about 70% and pitch-based carbon fibe...

AI Technical Summary

Problems solved by technology

But even if these conditions are set at the optimal value, the phenomenon of monofilament adhesion cannot be completely eliminated

Some people use to change the type of atmospheric gas, such as replacing air or oxygen with strong oxidizing ozone, sulfur dioxide or nitrogen dioxide, but because these gases are highly corrosive, on the one hand, the pre-oxidation equipment must be treated with anti-corrosion. It is also necessary to add special processing equipment to deal with these oxides after use, resulting in an increase in production costs

Others have proposed the technology of using anti-sticking agents such as silicon powder and oil to pre-treat the tow and then pre-oxidize the technology. Since these anti-sticking agents must be removed before the subsequent carbonization treatment, the complexity of the production process is increased. sex and production costs

It was also proposed to use rotating rollers, guide rollers, etc. to unweave the bonded fiber bundles, but this method cannot eliminate the defects that have formed on the fiber surface, so it will inevitably lead to low strength of the final produced carbon fiber